Magney House by Glen Murcutt an enduring testament to reverse brick veneer

Nathan Johnson

Since its 1984 completion, Glenn Murcutt’s Magney House has maintained a seminal presence in both international and Australian architecture circles.

In 1985 the NSW South Coast home received Australia’s highest residential design honour - the Robin Boyd Award for Residential Architecture—and has since been nominated by the Australian Institute of Architects (AIA) for a place on the International Union of Architects’ (UIA) World Register of Significant 20th Century Australian Architecture. Magney House is celebrated as one of Australia’s most influential and inspiring pieces of residential architecture.

Besides its acclaim and success in awards programs, which Murcutt now abstains from entering, Magney House most importantly meets what could be considered the natural criterion for outstanding architecture—it still functions according to brief after all these years.

One design element highlighted by the AIA as contributing to Magney House’s brilliance is its subtle management of heat load and intelligent passive design.

Murcutt used a combination of heavy north facing glazing with operable external shading elements, as well as a reverse brick veneer (RVB) walling system to control the heat load and internal temperature for Magney House.Magney House is situated 50m above sea level, faces due north and has a temperature range of up to 40˚C in summer to 5˚C in winter.

The northern and eastern facades of the long pavilion structure are entirely glazed and sit under a high eave. This layout encourages winter sunlight to penetrate the interior living spaces and warm the internal thermal mass. Conversely, in the summertime, the operable aluminium venetian blinds on the exterior block the light from entering and allow the insulated concrete floor and RVB walls to keep the interiors cool.

The all-important RVB wall is situated on the southern façade and consists of a three layered system. Beginning from the outside-in (and much like a lot of his other projects), Murcutt chose corrugated aluminium from Alucobond to make up Magney House’s external skin. Next a small cavity zone was formed with 37mm battens and filled with Insulwool 75 insulation. The final layer of the system is the painted single brick interior skin—the thermal mass.

Murcutt put the thermal mass for Magney House inside; an insulated concrete slab and reverse brick veneer wall act as a thermal battery for the home’s interiors.

Internal thermal mass works to even out the temperatures within Magney House. Murcutt knew that this works best when you insulate it from the outside. Original Glen Murcutt drawing courtesy of The State Library of New South Wales.

Murcutt is a long-time supporter for reverse brick veneer (RBV) in temperate climates and claims that the high percentage of air conditioned houses in NSW is an indictment on an architect’s inability to design buildings appropriate to place and climate.

"The problem we have mostly is the buildings we're putting up are totally inappropriate. From Darwin to Melbourne to Western Australia, it's a disease … They've all got to have air-conditioning because they're built the wrong way around."

Murcutt says the mass of material ought to be on the inside and the lightweight material on the outside so there is good insulation between the two, "so the outside takes up the thermal lag [and] the inside takes the response of all the internal factors so that you keep the hot sun out from the mass inside … so that in the summertime it's beautifully cool inside."

And that’s what he did for Magney House.

Magney House has been recognised internationally as an exemplar of outstanding architecture because of its simplistic and reductive design as well as its immensely considered response to its climate. Murcutt’s disinclination for mechanical air-treatment and his quest for a comfortable, low-maintenance home for his client led him inevitably back to the basic principles of passive design and in this case a reverse brick veneer walling system.